I suggest you ...

Move [REMINDER] word to the beginning of the subject line

the idea is simple, just moving [REMINDER] word in the subject line of the text reminders via email to the beginning.

Currently the reminders on email have the following format:

Subject line: Text text text [REMINDER]

I suggest to change it to:

Subject line: [REMINDER] Text text text

or even

Subject line: Reminder: text text text (with a bit different format style, as using CAPS LOCK is not the best idea as for me:)

Why it's so important?

This is much easier for eye to catch emails with a tag "reminder". When I see a new email, I read the subject line from left to right, so it would be much better to identify the emails as "reminders" from the very first moment of reading it.